Safety tube seal and process of its manufacture



Jan. 5, 1937. c. J. WESTIN 2,066,754

SAFETY TU BE SEAL AND PROCESS OF ITS MANUFACTURE Filed April 25, 1935 2 S heets-Sheefi i F/G..$'. F/G.6., F/a. 7

away I CZarks g zw ea /z v fa'gw Jan. 5, 1937. v c. J. WESTIN 5 SAFETY TUBE SEAL AND PROCESS OF ITS, MANUFACTURE Filed April 25, 1955 2 Sheets-Sheet 2 y i a Arrofiwfy.

Patented Jan. 5, 1937 UNITED STATES PATENT OFFICE SAF TUBE A PROCE S OF ITS MANUFACTURE A plication April 25 1933, Serial No. 667,824

12 Claims. (Cl. 113?121) This invention relates to improvements collapsible tubes and particularly to a new and useful, improvement in collapsible tube closures and t e m ho of ma ing ame Collapsible or flexible tubes are used as dispensing containe s for fluids or pas at r ls such as toilet creams, medicinal ointments, foods, extracts, e c.- he tubes a e u ua y m de of so e sui able o t meta o l y, but ay l be 10 m de o a fl xible or res lie t at ia suc as cellulose. o ot er synthe compounds Ea tube ,is'co nprised of a body portion with a relatively thin wall. 'Qne end of the tube is formed into a neck h ng a discharge ope a d provision for receiving a cap. The other end of the tube is left op n nt l h be is fil d. and then closed b mean o folds r tucks a e in t flattened out portion of the tube walls adjacent to the open end.

Heretofore, it has been the practice to make the closure by folding and bending the flattened end of the tub two, three, or more times and in many different ways, the fold usually extending completely across the flattened part of the tube,

25 and to reinforce and strengthen these folds reye se bends e tu ks have be n'r sort d t after the folds were made, the corners have been bent reverse y. diag a ly ac oss t e or ina ol In a large num er o tes s c n uct d with va ous types of tube closures I have found that the ma it o eaks at the ds o he f Close inspection of the tubes indicates that, when the walls are flattened, the stiffness and resiliency of the material causes an opening to be 35 formed at the crease, as indicated in the en- 'larged section (Fig. 4-). This opening'provides a ready passage for the breathing caused by temperature and climatic changes as well as the large number of leaks occurring at low pressures. While this is partly eliminated in tubes that have been cemented on the inside or coated with some form of latex, it is evident that any excess of cement or latex is squeezed out when the pressure is applied in flattening the tube walls 5 and there are no means possible of forcing this back to fill the crevice formed if and when the walls separate at the crease after the pressure is removed 1 For abetter understa ding o th atur of ,so-particular in erest in his desc p on the fo ds are referred to as elements of the tube closure, cemrris ng two th k sses of h at en d ll .cf the tube. By a tube referred to as having a dry closure is meant a tube being closed without 55 the use pf type .cf cement or latex on the a l. oihe tub or betwee the elements of h .fQld- By. a heat ea ed t b is meant n i which a thermalsplastic cement is used on the wall of the tube and between the elements of th told, and the s a ing s e d ythe ap :5. cation of heat after the'iolds are made. By a cement-sealed gr wet tube closure is meant a tube that, in gr during the process of filling and closing has some form of cement applied in liquid or pl st form a d as the f l s are completed the cement is placed between them and forms a strong bond between the elements of the fold.

In tubes sealed by having cement applied to the cutside, but between the elements comprising the told I ha e o tha t cement may not be of sufiicient quantity or it may not cover an area large enough to furnish adequate bond, even when caps of cement are formed over the side ends ofthe fold to give the required strength or high pressures and resistance against leaks,

sodesirable in many cases.

The purpose ,of this invention is to provide a tube having such a closure that the passage referred toabove is safely eliminated regardless of the type of closure used; dry or cemented.

I have found it a decided advantage to bend the corners over as shown in the drawings before making the standard fold in closing a tube. I haveuthus added an extra fold or element to the lCIQSlIIB without having to add any additional material in the length of the tube. Incidentally,

"this extra diagonal fold brings the hazardous corner away from the ends of the folds and increases the area of the bonded surface between the elements of the fold. It provides a crease diagonally across the passage referred to and places the terminal point of the original crease in the flattened wall a considerable distance in from the end of the fold and hides this terminal point inside of the folds. 40 1 have found that tucking the corners in is of decided advantage not only when cement sealing tubes but also when dry sealing, as it addsconsiderable tothe resistance against leaks even in the old type of tube closure. It is .evi- 5 and rever e bend o t9 th type us n extra a d fold as d scribed in Patent ol, 8..5. 2v2 ran d to me on April 5, 1932, or my eo nendin applicati n er al F r rth exposit on i m nv n n ference may be ha dto the annexed drawings and specification at the end of which my invention will be specifically pointed out and claimed.

In the drawings,

Fig. l is a diagrammatic view in side elevation.

Fig. 2 is a partial view in side elevation.

Fig. 3 is a diagrammatic face view.

Fig. 4 is a cross section on line 44 of Fig. 1.

Figs. 5, 6 and 7 are respectively face, side and face views illustrating the steps of the process.

Figs. 8, 12 and 16 are face views.

Figs. 9, 10, 11, 13, 14, 15 and 17 are side views illustrating the steps of another process.

Figs. 18 and 19 are respectively face and end views of a modification, and

Figs. 20 and 21 respectively are face and side views of another modification.

Referring to the drawings:

Fig. 1 is a side view of a collapsible tube I having the walls flattened at 35. Fig. 2 shows a side view of a tube having the corner bent at 36. Fig. 3 shows a face or front view of the tube with the corner bent at 36. Fig. 4 is a section on line 4-4 of Fig. 1 and shows the openings or passages along the'flattened portion of the tube at 38. Fig. 5 shows a front view of a tube in which the corners 36 have been bent further so as to form an angle of approximately 45 degrees with the standing part 35 of the tube wall. The standard first fold is usually made along the imaginary line 40 and the second fold along the line 4|. Fig. 6 represents a diagrammatic view showing a tube having the first fold partly made at 40 and the element 42 taking the position of about 45 degrees with the standing part 35 of the tube. The corner-fold 36 is shown here taking the position indicated at 39. This view also shows one way of applying a sealing cement to the elements of the fold, which here is indicated at 43 representing a brush or a spray nozzle. Fig. 7 shows a front View of the tube in the same position and at the same point in the process as in'Fig. 6. Fig. 8 is a front View in which the corner-fold along the line 31 has been completed so that the corner 44 is pressed tightly against the standing part 35 before the first fold along line 40 has been started. Fig. 9 is a side view of the tube in the same position and at the same point in the process as in Fig. 8. Fig. 10 shows the first bending along line 40 of the first fold which in this case may be considered as a second fold or the second element of the closure. Fig. 11 shows this second element bent closer towards the standing part 35 so as to form an angle of approximately 45 degrees into which a sealing cement may be applied by means of a nozzle or a wiper or spray gun or brush. Fig. 12 is a front view and Fig. 13 a side view of the completed first fold showing the corner fold or first element at 44, showing the second fold or element at 41, and showing the terminal or end of the tube at 1, the first two elements being pressed tightly against the standing part 35 of the tube. Fig. 14 is a side view showing the tube walls being bent at the line 4| in the process of forming the third element of the closure. Fig. 15 is a side view showing the continuation of the bending at 4| to form the third element so as to' at this point form an angle of approximately 45 degrees with the standing part 35 of the tube. Into this angle cement may be applied by anyone of the means referred to and here represented by a spray nozzle or like device at 49. Fig. 16 shows a face view of the completed closure and Fig. 17 a side view of the same. These figures show the finished closure flat at 50 without any form of crimp or corrugation. Fig. 18 is a face view and Fig. 19 an end view showing a finished closure which has been provided with crimps or corrugations at 5| and 52. Fig. 20 is a face view and Fig. 21 an end view of a tube to which a clip or reenforcing member 60 has been applied.

I do not intend to be limited in the practice of my invention save as the scope of the prior art and of the attached claims may require.

I claim:

1. A collapsible tube having one end sealed by a flattened portion, corners tucked in on diagonal lines, cement surrounding said tucked in corners, and a fold surrounding said tucked in corners.

2. A collapsible tube having one end sealed by a flattened portion, corners tucked in on diagonal lines, cement surrounding said corners, a fold surrounding said corners, and a second fold surrounding said first mentioned fold.

3. A collapsible tube having one end sealed by a flattened portion, corners tucked in on diagonal lines, a fold surrounding said corners, a second fold surrounding said first mentioned fold, and indentations formed in said folded end.

4. A collapsible tube having one end sealed by a flattened portion, corners tucked in on diagonal lines, cement surrounding said corners, a fold surrounding said corners, a second fold surrounding said first mentioned fold, and indentations formed in said folded portion.

5. A collapsible tube having one end sealed by a folded portion, corners tucked in on diagonal lines, a fold surrounding said corners, a second fold surrounding said first mentioned fold, and a clip of relatively rigid material surrounding said second mentioned fold.

6. A process of sealing one end of a collapsible tube which consists in flattening one end of said tube, bending in the corners of said flattened portion on diagonal lines, applying cement to said corners, and folding the end of said flattened portion about said corners.

'7. A process of sealing one end of a collapsible tube which consists in flattening one end of said tube, bending in the corners of said flattened portion on diagonal lines, applying cement to said corners, folding the end of said flattened portion about said corners, and folding another part of said flattened portion about said first mentioned fold.

8. A process of closing one end of a collapsible tube, folding in the corners of said flattened por- 1 tion on diagonal lines, applying cement to said corners, folding the end of said flattened portion about said corners, folding another part of said flattened portion about said first mentioned fold,

and producing indentations in said folded portions.

10. A process of closing one end of a collapsible tube which comprises flattening one end of said tube, bending in the corners of said flattened portion on diagonal lines, folding the end of said" manual handling and comprising in combination, a flattened portion of the walls of said tube in confronting relation, corners of said flattened portion bent on diagonal lines so that the edges formed from the open end of the tube are approximately parallel to the axis of the tube, a fold formed in said flattened portion of the tube and surrounding and enclosing said bent corners, and a coating or layer of cement surrounding said 7 corners and filling the inner surfaces of said fold 10 to retain said fold closed.

CHARLES J. WES'I'IN. 

